Sports Diver Knowledge Quiz

ST5 - Breathing Gas Planning and Systems

If you begin your dive with 210 bar of gas in your cylinder, what is the minimum amount of gas (in bar) should you plan to have left on reaching the surface at the end of your dive? Type only figures in the box. The question will revert to multiple choice after 3 attempts. See Student Workbook p82
1. 50
2. 52.5
3. 70
4. 140
Which surface breathing rate should you use when calculating the amount of gas required for a dive? See Student Workbook p83
1. 25 litres per minute
2. your actual surface breathing rate
3. your actual surface breathing rate or 25 litres per minute, whichever is the higher
4. your actual surface breathing rate or 25 litres per minute, whichever is the lower
Which of the following can increase breathing rates? See Student Workbook p83
1. Physical size
2. Fitness level
3. Energy output
4. Body temperature
5. Nervousness
6. All of the above
Your surface breathing rate is 20 litres per minute. How much breathing gas (in litres) is required for a dive to 30 metres for 20 minutes? Type only figures in the box. You will be shown the worked answer after 3 attempts.See Student Workbook pp82-85
1. 20 (breathing rate) x 4 (pressure) x 20 (time) = 1600
  add 50% reserve = 2400 litres
You plan to dive to 28 metres for 22 minutes with a surface breathing rate of 25 litres per minute. You have a choice of 10L, 12L, 12.5L, and 15L cylinders each filled to 220 bar. Which is the smallest cylinder that contains enough gas for the dive? See Student Workbook pp82-85
1. 10L
2. 12L
3. 12.5L
4. 15L
What breathing rate (expressed as litres per minute at the surface) are you advised to expect during the initial phases of an emergency? See Student Workbook p85
1. Your normal breathing rate
2. double your normal breathing rate
3. 25 litres per minute
4. 50 litres per minute
5. 100 litres per minute
How long (in minutes) would the gas in a 3L cylinder filled to 200 bar last in an emergency at 30 metres if the user's breathing rate (surface) was 50 litres per minute? Type only figures in the box. You will be shown the worked answer after 3 attempts. See Student Workbook pp82-85
1. Cylinder contains 3x200=600 litres
  Breathing rate at 30m = 50x4 = 200 litres per minute
  Gas will last 600/200=3 minutes
Which of the following AS configurations protects the wearer completely against 1st stage failure? See Student Workbook pp85-92
1. Octopus
2. BC demand valve
3. 2 independent regulators/single cylinder
4. manifolded twin cylinders
5. manifolded twin cylinders with isolation valve
6. independent twin cylinders
Which of the following AS configurations leaves both divers breathing from the same cylinder when it's in use? See Student Workbook pp85-92
1. Octopus
2. BC demand valve
3. 2 independent regulators/single cylinder
4. single cylinder plus pony
5. independent twin cylinders
What sort of regulator second stage is suitable for use as an octopus? See Student Workbook p88
1. An old but still functioning one
2. A new budget model
3. A high performance model
4. One of similar performance to the primary second stage
What sort of first stage is required for use with an octopus system? See Student Workbook p88
1. Any regulator provided it is in good condition
2. A new one
3. A high performance one
4. An environmentally sealed one